Electrically warmed mats or matting



Feb. 28, 1961 A. KELEMEN 2,973,425

ELECTRICALLY WARMED MATS OR MATTING Filed May 20, ,1959

Ufl tsd S e P m ELECTRICALLY WARMED MATS on MATI'ING Leslie AndrewKelemen, 19 Carlotta Road, Double Bay, near Sydney, New South Wales,Australia Filed May 20, 1959, Ser. No. 814,442 Claims priority,application Australia May 21, 1958 5 Claims. (Cl. 219-46) This inventionhas reference in general to mats and matting incorporating an electricalconductor which by radiation, applies heat throughout the whole orpractically the whole of their exposed surfaces.

In using the known forms of warmed mats or matting, it has been foundthat those articles tend to crease, with the result that, after thepassage oftime the electrical conductor or conductors incorporatedtherein tend to fracture, and this interrupts the flow of electricity orimpairs the heating efiect normally imparted by it.

The present invention has been devised in an attempt to prevent creasingof the mats or matting, at least in one direction, and it thus rendersthose articles more efficient as warming devices especially forincorporation in, or application to the upper surface of bed mattresses.

According to the present invention the mats or matting are made up of aplurality of threads which, in general, are woven much as ordinarily.However, those threads which constitute the weft are arranged inclusters alternately with one or more single strands; and the electricalconductor, which consists of a fairly fine flexible copper strand orstrands is enclosed, as a single thread or as a helix around a flexiblecore, in each of the beforementioned clusters.

Preferably the weft is of jute or other relatively inexpensive textilematerial, and it is intertwined by the warp threads as in normalweaving. When higher temperatures are to be provided for, the weft maybe of fibre glass or similar materials.

The warp threads of the mats or matting can be relatively thin, andpreferably they are of cotton or like strong material; though the warpthreads too, may be of fibre glass or similar materials when highertemperatures are to be provided for. The complete mats or matting arecharacterised in that the clusters of the weft threads create ribs atintervals throughout the material. Those ribs carry within them theflexible electrical conductor, and thereby serve to insulate and protectit. They also serve to minimize the possibility of the mats or mattingbeing creased longitudinally as distinct from transversely. That is tosay, in its application to a bed mattress the woven material ispermitted to crease transversely of the mattress; but provided it iskept reasonably flat as by tapes around its margin it will not creaselongitudinally of the mattress.

While the present invention has been devised primarily to provideimproved Warming mats for the upper surface of a bed mattress, ifdesired, they can be used to warm the upholstery of lounge chairs, andthe like. They can also be used under or incorporated in carpets orcarpeting to impart a uniform heating effect to enclosed apartments, theelectrical conductor in the mats or matting being connected to asuitable source of electric energy, if necessary through the medium of astep-down transformer or other appropriate electrical device of knowntype.

A further feature of the present invention resides in the fact that theelectrical conductor is formed helically and,

, 2,973,425 Patented Feb. 28, 1961 preferably, is wound around a j'utethread which constitutes a core for the conductor.

In order however, that the invention may be clearly understood andreadily carried into practical effect, reference is now made to theaccompanying drawings wherein:

Figure 1 represents the plan of portion of an electric mat constructedin accordance with one practical application of the present inventionand suitable for attachment to or incorporation in the upper portion ofa bed mattress.

Figure 2 is a section taken on the plane 2-2 of Figure 1.

Figure 3 is a magnified sectional fragment, in perspective, of the matrepresented by Figure 1.

Figure 4 is a view similar to Figure 1, but representing a mat whereinthere are eight weft strands between each cluster.

Figure 5 is a section taken on the plane 55 of Figure 4.

Reverting to Figure 1 it will be seen that the mat thereby representedis made up of a plurality of weft threads 10 and a plurality of warpthreads 11 interwoven by known weaving means. However some of the weftthreads 10 are arranged in clusters 12 as indicated in Figure 2: that isto say, in this particular form the mat, starting at the top edge, hastwo single weft threads 10 side by side. There is then a cluster 12 offour weft threads 10 and then two more single weft threads 10 and so on,alternately.

The beforementioned electrical conductor 13 is woven into the mat as aweft thread and passes from side to side of the mat within each cluster12.

In a practical application of the invention, adopted by way ofexperiment, the electrical conductor 13 consisted of eight twistedstrands of .0052 wire wound helically around a jute core, such as 14(see Figure 3). That arrangement proved quite satisfactory.

The exemplification of the invention illustrated by Figures 4 and 5 ismuch the same as that shown by Figures 1 and 2, but in that secondexemplification the mat has eight single weft threads 10 between eachcluster 12, instead of two.

The improved mats or matting can be heated by either AC. or DC. currentsupplied by normal electrical installations, through the medium ofvoltage break-down appliances of known type, care being taken to ensurethat the current cannot rise to a dangerous degree.

When intended for the warming of bed mattresses, the improved mats wouldbe furnished with suitable tapes, or other known fastening means such aspress-studs, so they may be secured to the upper surface of themattress. Alternatively, the mats could be incorporated in the mattressitself. 1

It will be appreciated that apart from their domestic uses, the mats ormatting may be employed for drying-out and other known purposes inindustrial establishments.

I claim:

1. An electric warming mat of Woven construction comprising a pluralityof weft threads arranged in clusters at intervals throughout the lengthof said mat and spaced by at least one weft thread, the weft threads ofeach cluster together being sufficiently stout to prevent formation ofcreases across them, and a flexible electrical conductor longitudinallyenclosed within said clusters and woven into said mat, said conductorelectrically insulated by the several weft threads constituting saidclusters.

2. An electric warming mat of woven construction as defined in claim 1,wherein said flexible electric conductor consists of a plurality of wirestrands wound helically around a weft textile thread constituting acore.

3. An electric warming mat of woven construction as defined in claim 1,wherein each of said clusters comprises at least four threads groupedtogether in parallel relation to each other and surrounding saidelectrical conductor throughout their length.

4. An electric warming mat of woven construction as defined in claim 1wherein said clusters create evenly spaced parallel ribs throughout thelength of said mat.

5. An electric warming mat designed to be attached to the upper surfaceof a bed mattress, said mat comprising a plurality of weft threadsarranged in clusters at intervals throughout the length of the mat, saidclusters spaced from each other by at least one weft thread, the weftthreads of each cluster together being sufficiently stout to preventformation of creases across them, a flexible electrical conductor woveninto said mat and longitudinally enclosed within said clusters andelectrically inuslated by the weft threads constituting said clusters,and means on said mat for fastening said mat to the upper surface of themattress.

References Cited in the file of this patent UNITED STATES PATENTS729,171 Herrgott May 26, 1903 1,368,412 Rohne Feb. 15, 1921 1,615,294Turver Jan. 25, 1927 2,490,417 Cochran Dec. 6, 1949 2,610,286 Cox Sept.9, 1952

